<!DOCTYPE html> <!-- Any copyright is dedicated to the Public Domain. - http://creativecommons.org/publicdomain/zero/1.0/ --> <html> <style> /* This is not a user agent style sheet, so the style will be ignored. "testing.supports.moz-bool-pref" is set to true in layout/tools/reftest/reftest-preferences.js. */ @supports -moz-bool-pref("testing.supports.moz-bool-pref") { p { background-color: red; } } </style> <body> <p>This text should not have background color.</p> </body> </html>